Tropical Weather Discussion
Issued by NWS

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41
AXPZ20 KNHC 171000

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1005 UTC Sat Mar 17 2018

Tropical Weather Discussion for the eastern Pacific Ocean from
the Equator to 32N, east of 140W. The following information is
based on satellite imagery, weather observations, radar, and
meteorological analysis.

Based on 0600 UTC surface analysis and satellite imagery through
0945 UTC.


A surface trough axis extends from 09N84W to 07N97W, where latest
scatterometer data indicates the Intertropical Convergence Zone
(ITCZ) begins and extends to 08N110W to 08N126W to 08N140W.
Scattered moderate convection is within 60 nm N of the axis
between 94W and 96W, and also within 60 nm of the axis between
130W and 134W.



A strong jet stream branch rounds the base of a broad deep layer
trough that is advancing eastward across the eastern portion of
the area. This jet stream is advecting abundant deep moisture
east-northeastward towards much of Baja California. Patches of
rain with embedded scattered scattered showers are being
transported east-northeastward to across Baja California. At the
surface, a cold front extends from a 1014 mb low over southern
California southwestward through 32N119W to 28N124W and to near
26N131W. This front will weaken is at moves across the remainder
of the northeast portion of the area and northern Baja
California by this evening. The interaction between thermal Low
pres over the far northern part of the Gulf of California and
high pres ridging just to the west of the Baja California
peninsula will result in strong southwest to west winds over the
waters N of 29N through early this afternoon, then diminish to
mainly moderate winds soon afterwards. The high pres ridging will
slide eastward through Mon in response to a strong cold front
that moves across the northwestern part of the area.

Pulses of strong winds are expected to the southwest off Los
Cabos early Sun, and off Cabo Corrientes by early Mon.


Over Gulf of Papagayo, high pressure ridging over the Caribbean
will bring fresh to strong NE to E winds through this morning and
again tonight and Sun night before diminishing to fresh winds.

Over the Gulf of Panama, fresh to strong northerly winds, with
seas of 5 to 7 ft will diminish to fresh winds this afternoon.
Seas will subside to 4 to 6 ft this afternoon.

Elsewhere, expect gentle to moderate winds and 4 to 6 ft to
persist into early next week.


Residual NW swell to 8 ft will persist south of 10N west of
about 136W through this evening, then decay below 8 ft. The
gradient associated with weak high pres over the area will
maintain gentle to moderate trades across the deep tropics along
with seas of 5 to 7 ft through Mon.

Farther S over the deep tropics, a broad upper trough in
combination with trade wind convergence is producing scattered
moderate to isolated strong convection within 30 nm of line from
11N111W to 10.5N115W. A stronger cold front will approach the far
NW corner of the area tonight. By early on Sun morning, low pres
will ride northeastward along the front to just N of the area
near 31N139W, with the cold front extending from it southwestward
to just west of the area. This cold front will be preceded by
strong to near gale force southerly winds and seas of 8 to 11 ft
as it reaches to near 32N136W to 27N137W, to beyond 26N140W by
Sun night and from near 32N133W to 26N135W to 24N140W by late Mon
afternoon. A secondary cold front will approach the far NW corner
of the area Mon night also preceded by strong southwest to west
winds, and most importantly a large batch of NW swell will
propagate into the NW part of the area ahead of the front on Mon,
with seas in the range of 8 to 14 ft. The highest of these seas
is expected in the far NW corner of the area on Mon.

Aguirre is the U.S. government's official web portal to all federal, state and local government web resources and services.